The present invention relates to aerosol dispensing devices, and in particular to actuator assemblies that provide a regulated time delay between the initial activation of the devices and the actual release of the aerosol contents to the ambient environment. More particularly it relates to devices that can be used with aerosol containers to dispense in this manner while providing a visual cue that the device is in the process of being activated. “Aerosol”, as used herein, includes all pressurized materials delivered in a manner or from containers and via actuators and other delivery systems comparable to those used with materials that literally form aerosols.
Aerosol containers dispense a variety of ingredients. One or more chemicals to be dispensed are usually mixed in a solvent and, in any event, are mixed with a propellant. Typical propellants are compressed air or other compressed gases, carbon dioxide, a selected hydrocarbon gas, or mixtures of hydrocarbon gases, such as a propane/butane mix. For convenience, materials being dispensed will be referred to herein merely as “chemical(s),” regardless of their chemical nature or intended function. Without limitation, chemicals can include actives such as insect control agents (e.g. a repellent, insecticide, or growth regulator), fragrances, sanitizers, cleaners, waxes or other surface treatments, and/or deodorizers.
The active/propellant mixture is stored under pressure in the aerosol container. The mixture is then sprayed out of the container by pushing down or sideways on an activator button, lever, or other structure at the top of the container that controls a release valve mounted at the top end of the container. The sprayed active may exit in an emulsion state, single phase, multiple phase, and/or be partially gaseous.
The aerosol container contents can be released via manual pressure (for as long as such manual pressure is provided). Alternatively, an actuator can be provided that latches or switches the release valve in an on position such that essentially the entire contents of the can are automatically dispersed in a single continuous, albeit elongated, burst (e.g. total release foggers), or by intermediate spaced bursts (e.g. automatic dosing systems).
U.S. Pat. No. 4,823,986 discloses a system for providing a time delay between the initial activation and the actual release of the contents. This provides the operator time to leave the immediate area to avoid being exposed to the chemicals being dispensed. This is especially desirable when the active being dispensed is an insecticidal fumigant. The disclosures of this patent, and of all other patents and patent applications referred to herein are incorporated herein by reference as if fully set forth.
For other time delay systems, see also U.S. Pat. Nos. 2,244,302 and 2,759,768, and (assigned to the assignee of the instant application) U.S. Ser. No. 10/845,692, filed May 14, 2004, for “Friction Resistant Time Delay Actuator Assemblies For Aerosol Containers”.
However, other delay systems have a variety of deficiencies. For example, once they are initiated there is some possibility that a user may be reluctant to leave the area because the user is not sure that the device is working. Such a user might therefore be exposed to the sprayed chemicals as a consequence of having stayed too close for too long.
In any event, many such systems are expensive to manufacture, rendering them impractical, and/or have other deficiencies. Hence, a need remains to provide improved, inexpensive, and reliable time delay systems for such purposes, and particularly systems that provide a visual cue as to when the delay period countdown has started.